I think they basically agree with your point here -- they mention Descartes and Kant to say roughly "I hold basically these ideas, but I don't mention the philosophers' names when I talk about them because 1) I came to them independently, and 2) the people I'm talking to are not familiar with the context so situating our conversation there isn't helpful." Their argument is that you can have philosophical conversations without relying on the context of the canon, and that in a first-level discussion they wouldn't bring up Descartes or Kant.